// Bucketlist tab — password-gated, real-time Firestore list
const BL_FB_CONFIG = {
    apiKey: "AIzaSyDuSjEGEKx5FnWYnQq8f_owbpYRBRrl5x0",
    authDomain: "esef-514bf.firebaseapp.com",
    projectId: "esef-514bf",
    storageBucket: "esef-514bf.firebasestorage.app",
    messagingSenderId: "353969651290",
    appId: "1:353969651290:web:41e3aaf8e54c743702a263"
};

// ═══════════════════════════════════════════════════════════
//  PASSWORD GATE — items never touch DOM until authenticated
// ═══════════════════════════════════════════════════════════

// --- SHA-256 via Web Crypto ---------------------------------------------------
async function sha256(text) {
    const buf = new TextEncoder().encode(text);
    const hash = await crypto.subtle.digest("SHA-256", buf);
    return Array.from(new Uint8Array(hash))
        .map(b => b.toString(16).padStart(2, "0"))
        .join("");
}

// --- Lock-screen HTML (only thing in DOM before auth) -------------------------
function showLock(container) {
    container.innerHTML = `
        <div class="bl-lock">
            <div class="bl-lock-box">
                <h2>Bucketlist</h2>
                <input type="text" id="bl-user" placeholder="Username" autofocus>
                <input type="password" id="bl-pass" placeholder="Password">
                <button id="bl-submit">Unlock</button>
                <p id="bl-err"></p>
            </div>
        </div>
    `;
}

// --- Build the real panel + attach Firestore after auth -----------------------
function unlock(container, db, hash) {
    container.innerHTML = `
        <div class="bl-panel">
            <div class="bl-list" id="bl-list">
                <p class="bl-empty">Loading...</p>
            </div>
        </div>
    `;

    const listEl = document.getElementById("bl-list");
    if (!listEl) return;

    // items live under bucketlist_data/<sha256(user:pass)>/items — the path IS the key
    db.collection("bucketlist_data").doc(hash).collection("items").onSnapshot(snap => {
        const items = [];
        snap.forEach(doc => {
            const d = doc.data();
            items.push({
                id: doc.id,
                title: d.title || "",
                description: d.description || "",
                date: d.date || "",
                utc: d.utc || "",
                done: d.done || false
            });
        });
        items.sort((a, b) => (a.utc || "").localeCompare(b.utc || ""));
        render(listEl, items);
    }, () => {
        if (listEl) listEl.innerHTML = '<p class="bl-empty">Could not load.</p>';
    });
}

function render(listEl, items) {
    if (items.length === 0) {
        listEl.innerHTML = '<p class="bl-empty">Nothing here yet.</p>';
        return;
    }

    // NOTE: item.done adds .bl-done class — hook for completed-item styling (CSS still TODO)
    listEl.innerHTML = items.map(item =>
        '<div class="bl-item' + (item.done ? ' bl-done' : '') + '">' +
        '<div class="bl-title">' + esc(item.title) + '</div>' +
        (item.date ? '<div class="bl-date">' + esc(item.date) + '</div>' : '') +
        (item.description ? '<div class="bl-desc">' + esc(item.description) + '</div>' : '') +
        '</div>'
    ).join("");
}

function esc(s) {
    if (!s) return "";
    return String(s).replace(/&/g,"&amp;").replace(/</g,"&lt;")
        .replace(/>/g,"&gt;").replace(/"/g,"&quot;").replace(/'/g,"&#39;");
}

// ═══════════════════════════════════════════════════════════
//  ENTRY
// ═══════════════════════════════════════════════════════════

document.addEventListener("DOMContentLoaded", () => {
    const tab = document.getElementById("bucketlist");
    if (!tab) return;

    if (!firebase.apps.length) firebase.initializeApp(BL_FB_CONFIG);
    const db = firebase.firestore();

    const container = tab;  // the <section> itself — nothing else exists inside it

    // --- Already authenticated this session? ---------------------------------
    const savedHash = sessionStorage.getItem("bl_hash");
    if (savedHash) {
        unlock(container, db, savedHash);
        return;
    }

    // --- Show lock screen ----------------------------------------------------
    showLock(container);

    const userInput = document.getElementById("bl-user");
    const passInput = document.getElementById("bl-pass");
    const submitBtn = document.getElementById("bl-submit");
    const errEl = document.getElementById("bl-err");

    async function tryUnlock() {
        const user = userInput.value.trim();
        const pass = passInput.value;
        if (!user || !pass) return;

        submitBtn.disabled = true;
        errEl.textContent = "";

        // hash = sha256("username:password") — both must match the Firestore doc ID
        const hash = await sha256(user + ":" + pass);
        try {
            const doc = await db.collection("bucketlist_auth").doc(hash).get();
            if (doc.exists) {
                sessionStorage.setItem("bl_hash", hash);
                unlock(container, db, hash);
            } else {
                errEl.textContent = "Wrong credentials.";
                passInput.value = "";
                passInput.focus();
            }
        } catch (e) {
            errEl.textContent = "Could not verify. Try again.";
        }
        submitBtn.disabled = false;
    }

    submitBtn.onclick = tryUnlock;
    userInput.onkeydown = e => { if (e.key === "Enter") passInput.focus(); };
    passInput.onkeydown = e => { if (e.key === "Enter") tryUnlock(); };
});